<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
 <head>
  <meta http-equiv="content-type" content="text/html; charset=UTF-8">
  <title>返回规范化的绝对路径名</title>

 </head>
 <body><div class="manualnavbar" style="text-align: center;">
 <div class="prev" style="text-align: left; float: left;"><a href="function.realpath-cache-size.html">realpath_cache_size</a></div>
 <div class="next" style="text-align: right; float: right;"><a href="function.rename.html">rename</a></div>
 <div class="up"><a href="ref.filesystem.html">Filesystem 函数</a></div>
 <div class="home"><a href="index.html">PHP Manual</a></div>
</div><hr /><div id="function.realpath" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">realpath</h1>
  <p class="verinfo">(PHP 4, PHP 5)</p><p class="refpurpose"><span class="refname">realpath</span> &mdash; <span class="dc-title">返回规范化的绝对路径名</span></p>

 </div>
 
  <div class="refsect1 description" id="refsect1-function.realpath-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="type">string</span> <span class="methodname"><strong>realpath</strong></span>
    ( <span class="methodparam"><span class="type">string</span> <code class="parameter">$path</code></span>
   )</div>

  <p class="para rdfs-comment">
   <span class="function"><strong>realpath()</strong></span> 扩展所有的符号连接并且处理输入的
   <em><code class="parameter">path</code></em> 中的 &#039;/./&#039;, &#039;/../&#039; 以及多余的 &#039;/&#039;
   并返回规范化后的绝对路径名。返回的路径中没有符号连接，&#039;/./&#039;
   或 &#039;/../&#039; 成分。
  </p>
 </div>

 
  <div class="refsect1 parameters" id="refsect1-function.realpath-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>

    
     <dt>
<em><code class="parameter">path</code></em></dt>

     <dd>

      <p class="para">
       要检查的路径。
       <blockquote class="note"><p><strong class="note">Note</strong>: 
        <p class="para">
         Whilst a path must be supplied, the value can be blank or <strong><code>NULL</code></strong>
         In these cases, the value is interpreted as the current directory.
        </p>
       </p></blockquote>
      </p>
     </dd>

    
   </dl>

  </p>
 </div>

 
  <div class="refsect1 returnvalues" id="refsect1-function.realpath-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   Returns the canonicalized absolute pathname on success. The resulting path 
   will have no symbolic link, &#039;/./&#039; or &#039;/../&#039; components.
  </p>
  <p class="para">
   <span class="function"><strong>realpath()</strong></span> 失败时返回 <strong><code>FALSE</code></strong>，比如说文件不存在的话。
  </p>
  <blockquote class="note"><p><strong class="note">Note</strong>: 
   <p class="para">
    The running script must have executable permissions on all directories in
    the hierarchy, otherwise <span class="function"><strong>realpath()</strong></span> will return
    <strong><code>FALSE</code></strong>.
   </p>
  </p></blockquote>
  <blockquote class="note"><p><strong class="note">Note</strong>: <span class="simpara">
因为 PHP 的整数类型是有符号整型而且很多平台使用 32 位整型，对 2GB
以上的文件，一些文件系统函数可能返回无法预期的结果 。</span></p></blockquote>
 </div>

 
 <div class="refsect1 changelog" id="refsect1-function.realpath-changelog">
  <h3 class="title">更新日志</h3>
  <p class="para">
   <table class="doctable informaltable">
    
     <thead>
      <tr>
       <th>版本</th>
       <th>说明</th>
      </tr>

     </thead>

     <tbody class="tbody">
      <tr>
       <td>5.3.0</td>
       <td>
        在之前的版本中，在 *BSD
   系统上，如果仅仅是 <em><code class="parameter">path</code></em> 不存在的话，<span class="function"><strong>realpath()</strong></span>
   并不会像其它系统那样返回 <strong><code>FALSE</code></strong>。
       </td>
      </tr>

      <tr>
       <td>5.0.0</td>
       <td>
        在此之前的版本中，如果 <em><code class="parameter">path</code></em> 传入了空或者 
 <strong><code>NULL</code></strong>，将导致 <span class="function"><strong>realpath()</strong></span> 返回脚本当前的目录。
       </td>
      </tr>

     </tbody>
    
   </table>

  </p>
 </div>


 <div class="refsect1 examples" id="refsect1-function.realpath-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-2361">
    <p><strong>Example #1 <span class="function"><strong>realpath()</strong></span> 例子</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />chdir</span><span style="color: #007700">(</span><span style="color: #DD0000">'/var/www/'</span><span style="color: #007700">);<br />echo&nbsp;</span><span style="color: #0000BB">realpath</span><span style="color: #007700">(</span><span style="color: #DD0000">'./../../etc/passwd'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
/etc/passwd
</pre></div>
    </div>
   </div>
   <div class="example" id="example-2362">
    <p><strong>Example #2 Windows 上的 <span class="function"><strong>realpath()</strong></span></strong></p>
    <div class="example-contents"><p>
     在 Windows 上，<span class="function"><strong>realpath()</strong></span> 会将 unix 风格的路径改成 Windows 风格的。
    </p></div>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #007700">echo&nbsp;</span><span style="color: #0000BB">realpath</span><span style="color: #007700">(</span><span style="color: #DD0000">'/windows/system32'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>以上例程会输出：</p></div>
    <div class="example-contents screen">
<div class="cdata"><pre>
C:\WINDOWS\System32
</pre></div>
    </div>
   </div>
  </p>
 </div>

 
  <div class="refsect1 seealso" id="refsect1-function.realpath-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="function.basename.html" class="function" rel="rdfs-seeAlso">basename()</a> - 返回路径中的文件名部分</span></li>
    <li class="member"><span class="function"><a href="function.dirname.html" class="function" rel="rdfs-seeAlso">dirname()</a> - 返回路径中的目录部分</span></li>
    <li class="member"><span class="function"><a href="function.pathinfo.html" class="function" rel="rdfs-seeAlso">pathinfo()</a> - 返回文件路径的信息</span></li>
   </ul>
  </p>
 </div>

 
</div><hr /><div class="manualnavbar" style="text-align: center;">
 <div class="prev" style="text-align: left; float: left;"><a href="function.realpath-cache-size.html">realpath_cache_size</a></div>
 <div class="next" style="text-align: right; float: right;"><a href="function.rename.html">rename</a></div>
 <div class="up"><a href="ref.filesystem.html">Filesystem 函数</a></div>
 <div class="home"><a href="index.html">PHP Manual</a></div>
</div></body></html>
